


Dear Diary: Today I Conquered the World

by alephthirteen



Category: Harry Potter - J. K. Rowling
Genre: BAMF Harry Potter, BAMF Hermione Granger, Death Eaters Understand Fear and Violence, F/F, F/M, Femme Fatale Ginny Weasley, Harry and Hermione Have Always Been Friends, Harry and Hermione are not Purebloods, Hermione Brought Both, Hermione Holds the Pursuit of Knowledge Above All, How Can You Know a Spell is Evil if You Don't Cast It, Misuse of Dark Magic for Sexy Reasons, Misuse of Muggle Science for Nasty Reasons, No-Holds Barred Golden Trio, Processed In Factory that Also Produces Plot, Shameless Smut, They have more to lose than Ron does, Voice of Reason Ronald Weasley, Voldemort Didn't Exist in a Vacuum, this is war
Language: English
Status: In-Progress
Published: 2021-01-01
Updated: 2020-12-31
Packaged: 2021-03-10 22:48:10
Rating: Explicit
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 3
Words: 3,758
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/28461144
Author URL: https://archiveofourown.org/users/alephthirteen/pseuds/alephthirteen
Summary: Hermione's mother and father are oral surgeons for the National Health Service, contracted to provide dental care to members of the Royal Marines.  Corporal Vernon Dursley is a mess sergeant who's out of shape, a shit cook, and probably a drunk.  At least he isn't around much and Petunia's too busy trying to look respectable on an enlisted man's salary.  Harry instead finds himself brought up by the rough, randy, and hot-tempered servicemen milling around the base.  The girlfriends, floozies, and whores make a project of the wandering, sweet-hearted little rascal.To her parents' chagrin, Hermione likes to wrap up her day at her posh school by walking over to the bases' schools to play with children there.  One of those children is a Harry, a shy, smart boy who doesn't get enough to eat and likes this strange, brown-haired girl who gives him books.One day, a flock of owls takes over the commandant's office and refuses to leave.  Each one carries a letter...ORHarry and Hermione knew each other as kids and Harry's young life makes him unwilling to lie down and act out a prophecy.ORHarry decides to make use of the knowledge Tom riddle left in his diary.
Comments: 5
Kudos: 36





	1. Rough Start

**Author's Note:**

> I find the concept of writing a "Dark Harry" fascinating. Does he have to be mustache twirling, puppy stomping evil? Or does ruthlessness in his methods suffice?
> 
> In duels, Harry never uses any other spell besides Expelliarmus because he 'doesn't kill'. Except probably has killed many times. He killed Quirrell midway through his first year (in self defense) by holding on to his victim while he screamed until he _stopped screaming_
> 
> He's knocked enemies off of brooms in midair. He's left Dolores Umbridge alone in a forest with centaurs she's been harassing (though the books implies she only gets raped to insanity).
> 
> He's not a bad person because of this, necessarily. He's someone who's lived in kill-or-be-killed mode between ages 11 and 18 and by the time he's come out the other side, he's killed or placed people in situations where death is essentially certain several times.
> 
> The books use a very oversimplified morality: anyone who kills is a villain, anyone who refuses to kill is a hero.
> 
> Is Molly Weasley a bad person for killing Bellatrix? Dumbledore, for having Barty Crouch Jr. executed by Dementors? Is Hermione a bad person for essentially _turning her parents into different people_ by making them people who aren't even aware they are parents, taking away all the life experiences around their daughter? They'd probably have taken death, over not remembering their little girl.

**Summary for the Chapter:**

> Where Hermione slums with a poor kid and it takes a village to raise a Harry

**Notes for the Chapter:**

> Alan Alda, the actor of MASH fame, was raised in a burlesque house. Quite a sensitive, soft spoken man. That's where I'm getting my inspiration here for Feral!Harry. The older brothers getting him into trouble are off duty Marines, ne'er-do-wells but not criminals.
> 
> The older sisters keeping him from doing anything too stupid range from housewives he pulls weed for to strippers who slip him some pocket money to let the air out of some pervert's tires.

**Plymouth, Devon - 1991**

Near Stonehouse Barracks, home of the 3 Commando Brigade, Royal Marines

It's cold. Wind off the sea carries stinging, salty chill up over the docks and into the town. Harry stuffs his hands deeper in his pockets, relishing the lambskin lining of the old jacket. Bomber pilot's jacket, from back in the War. Back when pilots didn't have tray tables, or autopilots, or radar. They had coats and earmuffs and Nazi fighters shooting at them.

Old Lady Rose gave him this for fixing up her back porch. She gave him the pants _last_ winter because she felt sorry for him. He does look a bit like her Jimmy did, back when. Jimmy and Rose met young, so their first photos are seventeen or eighteen, before he shipped out to train during the blitz. Scrawny fellow with messy black hair and glasses. 

Dudley's hand me down windbreaker is worn thinner than a sheet. It's nothing compared to this, so he stuffed it in his backpack. He'll have to hide this somewhere when he gets home. Shouldn't be too hard. Payday was day before yesterday, so Uncle Vernon was drunk _yesterday_ and today he'll be getting hammered by his commanding officer. Probably fell over and contaminated the food with his fat face. The fact that the Royal Marines can't find a better cook than Vernon Dursley really says a lot.

When she realizes her shopping trip is canceled because Vernon drank it all, Aunt Petunia will be fit to whip _Dudley,_ let alone Harry.

No, better to see if any jobs need doing. Show up home in a couple days.

"Hey, Jack!" Harry calls out.

The bent-over old man sweeping out his automat gives a quick wave.

"Gutters all right?" Harry adds over the wind.

"They'll keep, young sir," Jack chuckles.

"Don't call me sir!" Harry jokes. "I work for a living."

"Brat," Sarah huffs, swatting her husband and then Harry with a ladle.

"I come in peace," Harry promises, backing away.

"See that you do," she huffs, waving the gravy-dripping implement.

There's no one in the park. Usually, he'd wander back to the base's fence. See if any of the lads have any trouble they think he should get into. Aaron wanted to take Harry hunting, which sounded like fun. No sense doing that today because with Vernon getting chewed out, Harry's more likely to get spotted and have someone who 'means well' drive him home because they think he's waiting for a ride.

"Hey!" a voice calls out behind him.

Harry spins around.

Flying up the street with her messy brown hair bouncing behind her is his best friend. Hermione Granger. She's a year older than him and her parents are rich--doctors at the base hospital--but they get along great. Hermione has books she's tired of reading and Harry has never heard of any of those books. For his part of the bargain, Hermione wants 'girly stuff' even though hates the girls at her school. So he gets her castoff books and she gets makeup and fashion magazines and things she'd rather not ask her mum about. Hermione says her mum will think she's a failure if she puts on makeup before graduating Oxford.

Harry doesn't have a library card or a friend his own age.

Hermione has piles of used paperbacks and the girls her own age bother her.

She's huffing in the cold air, making little clouds as she scrambles along under her massive backpack. She switched her school shoes for trainers but for some reason didn't think to put on actual _pants_ over her skirt.

Harry, by virtue of being unofficial kid brother to a few hundred marine cadets, is friends with some odd sorts. His odd jobs aren't just old lady's porches and automat gutters. He's got a knack for wires, if he says so himself. He's cheap and he's careful and he doesn't ask for money unless he fixes it. So he's got a lot of clients in town, including the madams of both of the brothels that don't _technically_ exist. Some of the businesses who'd rather not have the cops around have asked Harry to fix their lights. He's never seen a girl naked, but he's wired up a red neon light _shaped_ like one for a hundred quid. 

"Got them?" she huffs.

"Someone's pushy," he jokes.

"Someone is freezing," she whines.

Harry takes Dudley's ratty old windbreaker out of his rucksack and opens it up. Inside are several tubes of lipstick, a compact mirror

"I wasn't sure but I talked to one of the girls," he admits, his cheeks quite pink. "Told them what you look like."

"You talked to one of the girls?" she squawks. "About me?"

"Not your name! I don't know what lipstick looks good with brown hair, do I?" he complains.

"I better not come out looking like a whore," she huffs. 

"Well, the whore I asked said that's really more about how much you use. And where. But she did say she'd give you a tutorial."

Hermione punches his arm.

"Wanker."

"Ooh, new word!" He teases. "Get that hanging around the back fence near the motor pool, like I did?"

"Mum," she says with a blush. "Someone was trying to make her re-use supplies. Unsanitary. Called him a wanker and asked if he'd be fine getting a shot with a syringe that had been in the butt of a patient of her choosing."

"Got a new book you'd like," she jokes.

"Oh?"

"Yeah. Couple. _Lord of the Rings_..."

"Classic," Harry jokes. "Not that I've ever read it. Just heard of it."

"And this new book called _Game of Thrones_. You cannot tell anyone I gave this to you. It's really violent and my mom shouldn't have bought it for me in the first place."

"I'll only read it with supervision," he promises. "I'm safe from a book as long as I've got _Hermione Granger_ to help me."

"Library?" he suggests.

"Sounds good."

\-----

"Since when do a hundred owls nest on the old barracks?" Harry mutters, pointing up the hill.

"Huh?" Hermione asks, looking up from the compact mirror. "Whoa. Weird."

A hundred feathered heads turn as one. The owls leap into flight, heading straight for them.

"Run!" Harry shouts.

**Notes for the Chapter:**

> The first book of the Song of Ice and Fire saga (Game of Thrones), came out in 1991, which is the same year that HP canon kicks off.


	2. Hoarding Resources

**Summary for the Chapter:**

> Where there are no unfair advantages.

**Hogwarts - 1992**

Chamber of Secrets

Fawkes coos, nudging Harry with his beak.

Basilisk venom sizzles through his veins. He hopes it kills him soon because he'd rather not puke again, especially after so much got in the gaping hole in his arm.

"Her first," he croaks, nodding to Ginny.

The bird hops over and drips seven tears onto her lips. She stirs. Fawkes comes over and does the same for him, this time straight into the wound.

"Harry?" she groans.

"Yeah."

"T-t-the diary," she chokes. "It made me."

"I know, Gins. I know. Not your fault."

"I'll get rid of it," he promises her, holding out his hand.

He lifts the fang as high as he can and swings down. He misses the diary almost entirely, shattering the fang on the stone. A single splinter pierced the spine of the book, but just barely.

 **NOOOO!** Someone shouts in his head. It sounds like they're being tortured.

"Fawkes?" Harry groans. "Can you help us back?"

The phoenix chirps happily.

\-----

"Voldemort's diary?" Ron sputters.

"You're not keeping it?" Hermione demands. "You have to give it to McGonagall."

Harry hands Hermione a notebook.

"Ten flashiest, most powerful elemental spells known to wizard kind. Enjoy. One for each birthday I needed to catch up."

Her eyes light up and she snatches the book before Ron can get it.

"How?"

"He's trapped in a diary. But in my scar, I can hear him. He's in an enchanted diary that can only be destroyed by basilisk venom and maybe two or three spells. It's really easy to _hurt_ a book, even if I can't destroy it. He'd rather answer a few questions than have me pour bleach on it again. Seemed to make him pretty barmy when I bleached all the ink off."

"How come he can't just take you over," Hermione asks. "Like he did Ginny?"

"Dunno. He's tried. Heard him bitching about failing all through last night."

Harry pokes the booby-trapped box the diary is in. It cost about a thousand galleons and Dumbledore had to sign for it. But it's supposed to be impossible to escape from inside.

"That's mental!" Ron shouts.

"It is a bit...much," Hermione agrees.

"Hermione," Harry says, rolling her eyes. "Are you or are you not playing with a baby dragon made entirely of Fiendfyre?"

She blushes, waving her wand and sending the miniature dragon into the fireplace, where it clambers up the chimney and trills happily. Molten brick drizzles down into the floo.

"She's cute. Also, apparently you can make them in different colors," she chortles.

"She?"

"Her name is _Flicker,_ Ron."

Ron frowns.

"Fiendfyre's a nasty spell, mate."

"All of the dueling spells that can actually hurt a person started as Dark magic," Harry reminds Ron. "All weapons are nasty. He's already after us. One little piece of him is here. It knows more about magic than everyone in this school put together. Maybe including Dumbledore. We keep it, we get as much information out of it as we can. We don't cast any spell or make any potions unless we vote on it. Anything that might kill someone, we all need to vote yes. Agreed?"

Ron pulls at his hair.

"Why do your ideas scare me so much?"

"We do this," Hermione sighs. "We might all end up going full-on Dark."

Harry sighs.

"I know. But I'm not sure I had an option not to. I've had part of this clown burned onto my forehead since before I could talk. He's probably been warping my brain since before I could speak. This just gives me control over what evil ideas he's giving me. You two are welcome to walk away, or try and find another way to fight him. We'll still be friends."

"Ron, if you don't want to be a part of it," Hermione offers softly. "We could lock the memory off."

Ron groans.

"Fine! I'm in."

"Be the death of us, this girl," he grumbles, nodding at Hermione.

"Probably," Harry chuckles.

"You really shouldn't have been friends before you met me," he grumbles.

* * *

**Riddle Manor - 1995 - Wiltshire**

Harry's wand goes tumbling out of his hand as the vortex dumps him ass-over-head into the smelly, wet moss. The Triwizard cup lands a hundred feet off and bounces down a sloping lawn. He's at the edge of a graveyard. There's shapes moving in the distance. Men with black cloaks, or just dark blue bedsheets on a line. Too dark and too far to tell.

Unfamiliar terrain. No weapon. Nighttime. Bad fucking mixture.

Cedric Diggory comes screaming out of the same vortex, narrowly missing going skull-first into a mausoleum. He starts pushing himself up.

"Down, Cedric!" Harry shouts, shoving his friend's head into the grass.

"What the _fuck_ ," he snarls.

"Shh. Cup was fucked with," Harry whispers. "Portkey, I think. We let go early, so we're a ways off where we should be. I don't know where we are, I can't reach my wand without leaving cover, and someone brought us here as a trap. Lucky for them, I'm too stupid to use a portkey right so they're about a quarter mile away at the opposite end of the graveyard. We can't get to the cup unless we fight them and we've got nothing to fight _with_ unless we go looking."

"All right," Cedric mutters. "You're the idiot who went down into the Chamber of Secrets. Lead on."

"Right," Harry mutters. "Stay low, don't make much noise. Don't touch your wand unless you have to. Lots of lethal curses fire straight. Like an arrow or a bullet. So keep your head behind something harder than it is, yeah?"

Cedric nods.

Harry has a _hunch_ why he's here. There's only so many spells that can turn a shade into a body. Blood, bone and flesh is one. Any number of Death Eaters would cut their own balls off if asked, so that handles flesh of the servant. Bone of the father, he realizes, means that they must be somewhere Voldemort's family used to live. Blood of the enemy? That's just extra motivation to _not_ get himself hurt tonight.

Harry looks around as far as he can without breaking the dandy cover provide by these two headstones. Run down manor on the hill. Ruined town maybe an hour's walk away. One big building near the edge. Soccer pitch. Unusually large parking lot.

"Right. I'm going to guess," Harry mutters, glancing around the corner with a hand mirror Ginny gave him. "That that cauldron's going to get up to some nasty business tonight. But there's no one here _yet_ because they either don't know we're here or haven't found us. I can't apparate and you don't know where we are, so we're buggered if we try and run."

"Yeah," Cedric agrees."

"So I say we make for the town. See if there's a phone. Go to the school, ransack the chemistry lab, and see what we can do to sour their potion. If we're lucky, there's some acids left in the chemistry classroom. Sound good?"

Cedric nods.

"Come on. We'll head for those trees. Leaves are wet, so we shouldn't have to worry about crunching and getting heard."

"Where the hell did you learn this stuff, Potter?"

"Muggleborn orphan secret," Harry jokes.

"If we're still alive," Cedric grumbles. "I'm writing the queen to have you named king of the muggles."

 **Tell him,** the scar whispers. **Tell the nice lad from Hufflepuff how you keep slipping through my fingers...**

 **You're useful,** Harry reminds Tom's fragment. **You're not indispensable.**

\-----

There's no working phones in town. No petrol in the pumps, either. Shotgun behind the counter but Harry doesn't like the look of the box of twenty-year old shells. In the City Hall, there's a display case with a pair of Webley revolvers in the Constable's office. Mark VIs with 1942 manufacturing dates and fancy Royal Navy inlays on the grips. No cartridges. Probably surrendered when the guns went into the cases after the laws changed.

Harry takes both as a souvenirs. Maybe he can find a cowboy hat and a long coat somewhere.

"Why are you taking those?" Cedric whispers.

"Because I feel like it," Harry whispers back. "Because if I ever find myself in a pinch without a wand but _with_ this, I can blow a Death Eater's guts open. And then I'll think 'thanks, past Harry'. Plus Ron's dad likes to tinker with muggle shit and if I nick his notebooks, I can probably fix them up for magic bullets."

"No shit?"

"Heard the Beauxbatons students going on about riflery classes. So they must use guns over there..."

Cedric gives him a slanted grin.

"And what were _you_ doing near the carriage? Were you spying on the nice ladies?"

"I was helping Gabrielle back from the second task. She sort of glued onto me and wouldn't let anyone else walk her back."

One of the cloaked figures strolls down the street. Cedric's a quick leaner, so he ducks down without being made to. The masked figure finally turns around and walks back.

"Patrol," Harry whispers. "They must have found the cup and wondered where we went."

"Come on!"

\-----

"They cleared out in a _hurry,_ " Harry says, glancing around the science classrooms.

"This place is creepy," Cedric whines. "I've been in a few muggle buildings but this place is...ugh. It's like the Shrieking Shack, I swear to Merlin."

Harry looks up from the drawer he was rifling through.

"I bet that's why! If this is Voldemort's home-town, then probably the muggles just got spooked. Cleared out."

"Yeah," Cedric shudders. "They don't notice much but you couldn't miss that kind of _wrong_ in one place."

Most of the chemical vials have been emptied, or cracked.

"Bugger me sideways," Harry whispers, throwing open the last cabinet.

"What?"

"Nitric and hydrochloric acid," Harry replies. "Let's see..."

_Four liters nitric, one hydrochloric. Perfect._

"Mix these and you get aqua regia. Powerful acid."

"How do you know this?" Cedric teases.

"When Hermione freaks out, I make her tell me a fact that she doesn't think I'll know. Picking one calms her down. This stuff is crazy. It will dissolve gold, silver, copper, tin. Muggle scientists use it to discover new metals because it melts whatever rock they toss in it."

"So?"

"So, if we take the caps off these and pour them into the cauldron, it'll _melt the fucking cauldron_ and anything inside it."

"Oh."

"Yeah, oh," Harry chuckles.

"You're an odd wizard, you know that?"

"Help me carry them."

\-----

Pettigrew draws a nasty silver knife from his robes. From his spot in the trees, Cedric glances at Harry. Harry shakes his head.

Harry really hopes his five-minute crash course on using a shotgun sunk in. He led the Death Eaters on a chase so Cedric had time to rig up the jugs on the branch of a dead oak that hangs high over the cauldron. Cedric tucked his own wand into some vines near the base of Tom Riddle Snr.'s grave. Harry has managed to get it _almost_ into his sleeve at this point.

Hopefully a Huffepuff's wand knows a friend in need.

"Blood of the enemy _,"_ Pettrigrew snarls. "Forcefully..."

He slashes Harry's arm.

"...taken."

He drops the blood-smeared knife into the cauldron.

"Now the dark lord rises!"

 _Give it a minute,_ Harry reminds himself. _We need him alive so he can die again._

 **I might have been lying,** his scar reminds him. **Why wouldn't I have?**

**Because, Tom, you're trapped in a ratty old diary in a box under my bed with an ever-burning candle under you. The only way the pain stops for you is if I let the diary be destroyed, which I can't do if I'm dead.  
**

**FOOL BOY!** Voldemort's ghost snarls. **I WILL ESCAPE! I WILL DESTROY YOU!**

His scar lights up with pain.

"FIRE!"

Cedric fires both barrels, igniting the other shells tied around the branch and cracking it. The branch snaps and punctured jugs of industrial acid tumble into the cauldron.

"Avada Kedavra!" Pettigrew shouts, aiming into the trees.

Given that a body with a Hufflepuff-yellow T-shirt doesn't fall out, Harry thinks he missed.

Inside the cauldron, something _shrieks_ in pain.

"M-m-master?" Pettigrew whimpers, taring over the rim.

"DIE!" Cedric shouts, running out of the woods with the empty shotgun over his head like a club.

" _Expelliarmus_!" Harry shouts, flicking Pettigrew's wand far into the distance.

Cedric cracks Pettigrew on the back of the head and he topples over into the rapidly-melting cauldron.

"Grab the cup," Harry pants.

* * *

**Notes for the Chapter:**

> Harry is torturing Voldemort for a dump of all the magic he knows and taking copius notes. Hermione's in it because she likes to learn shit. Ron's going along because they're his friends.
> 
> This will be fine, I'm sure...


	3. Coming Clean

**Summary for the Chapter:**

> Where the closing ceremony of the Triwizard Tournament goes very differently.

**Hogwarts - 1995**

He remembers grabbing the portkey and closing his eyes, hoping that none of the spells hitting the gravestones would hit him and kill him mid-transit. He hears a snap and the right side of his body is sizzling with pain.

"Merlin!" someone shouts.

"How'd they get here?"

"'Elp zem!" Madam Maxine shouts.

"Harry?" Hermione whispers.

"Mate, you good?"

The next voice is Dumbledore's.

"Harry, my boy, are you all right?"

He shakes his head.

"Voldemort," he whispers. "I saw him."

"THAT'S WHO THAT WAS?" Cedric hollers.

Harry opens his eyes and realizes with a shudder that he's basically lying on top of the Hufflepuff seeker, curled into a fetal position.

"Harry," Cedric teases, all grin. "Buy a bloke dinner first."

"Right," Harry mumbles. "Sorry, mate."

Amos Diggory throws his arms around his son before poor Cedric can get even halfway up.

"The cup was a portkey. Ingenious."

"Severus?"

"Yes, Headmaster?" Snape drawls.

"I presume you did not do this?"

"I assure you, any trap I created for Harry would be one I could monitor and would have more..."

Snape smiles.

"...finality."

_Is Snape teasing me? Not hating? Teasing?_

"I see. Well, I think I need to have a faculty meeting, then."

Dumbledore turns away to speak to the others and Madam Pomfrey is hurrying his way in a way that tells him he won't be eating solid food or seeing outside for a week.

"Headmaster!" Harry calls. 

Dumbledore turns around.

"Yes, Harry?"

"After, I need to talk to you. We do. Me, Ron, Hermione."

"Of course, dear boy. Minerva? Severus? Follow me, please."

\-----

"So _Mad-Eyed Moody_ is a Death Eater?" Ron asks, eyes wide as plate. 

"Honestly, Ronald. It was probably someone using a Polyjuice potion."

"Barty Crouch Jr. and he put up rather an energetic fight," Dumbledore grumbles, rolling the wrist on his wand hand.

"And rigged all that up so that Harry would be nose-to-nose with you-know-who?"

"Actually Mr. Weasley, towards the end," Dumbledore jokes. "Tom's nose disappeared. Wish the Department of Mysteries had let me examine the corpse."

"Corpse?" Harry blurts out.

"I think it's safe to say he's as dead as he was before. The spell worked, in that it gave him a physical body. Your trick with the...acid, was it?"

"Yes, sir."

"Meant that said body never made it very far. I do have to ask, my boy, how you knew to have Cedric booby trap the _cauldron_ ahead of time. Last I recall, Necromancy was not a class offered here."

"Well, sir...we," Harry stammers. "The three of us..."

"Oh no, mate," Ron huffs, crossing his arms. "This is all you."

Harry tells him. About the diary. About using it. About some of the spells they've learned, above their grade level and good and not-at-all-good. Expects the worst. Expects a beating, like Petunia or Vernon.

"I see," Dumbledore finally replies. "I would like to think on this a while. I assume the diary is safe?"

"Yes, sir. That weird extendable box I told you was for the invisibility cloak."

"Ah. Yes. Clever. Mad-Eyed Moody favors those, actually. You might enjoy meeting the real one, once he's recovered. I will not be taking the diary from you at this time, Harry. Not as if I could destroy it if I did, and he can speak to you through the scar at any time. I would encourage you to leave it sit for as long as you can. A great many things in life are easier to manage if one doesn't do them every day. Discipline is a marvelous shield against both one's enemies and oneself."

"Except some things you have to do every day. Like eating," Ron huffs.

"Quite, dear boy."


End file.
